This week in science is a review of the most interesting scientific news of the week.

Fish swims around healthy coral on the Australian Great Barrier Reef.
Credit: Tane Sinclair-Taylor/ARC Center of Excellence via AP.

Bleaching has resumed on Australia’s Great Barrier Reef

Coral reefs are diverse underwater ecosystems developed inside and around calcium carbonate structures secreted by corals, which are marine invertebrates. Those reefs provide a home for at least 25% of all marine species but are extremely sensitive to temperature variations.

Healthy reefs on the Australian Great Barrier Reef.
Credit: Tane Sinclair-Taylor/ARC Center of Excellence.

The current trend of rising ocean temperatures is increasingly causing these otherwise colorful ecosystems to die, a process called bleaching. The hotter water stresses corals, which then expel the colorful algae living inside them. Therefore, corals themselves become more vulnerable to disease and death.

Last year marked the worst bleaching event ever registered in Australia’s Great Barrier Reef. According to Professor Terry Hughes, from the ARC Centre of Excellence for Coral Reef Studies and leading author of a study relating global warming and recurrent mass bleaching of corals, whose findings have been published in the scientific journal Nature:

"We're hoping that the next 2-3 weeks will cool off quickly, and this year's bleaching won't be anything like last year. The severity of the 2016 bleaching was off the chart. With rising temperatures due to global warming, it's only a matter of time before we see more of these events. A fourth event after only one year is a major blow to the Reef."

Corals can recover from bleaching, but it is a process that takes them years to complete. Unfortunately, those bleaching events appear to be happening more frequently over time. The first two major events occurred back in 1998 and 2002, with the worst happening in 2016. But now, scientists are preparing for another huge bleaching again this year. Such back-to-back bleaching events could lead corals to finally die, with big consequences for the ecosystem they sustain. According to coral reef scientist Julia Baum of Canada's University of Victoria:

"None of us were expecting the water to be heating up again right now. I think it's beyond what any of us could have imagined. It's our worst nightmare."

Dead staghorn coral killed by bleaching on the Australian Great Barrier Reef. Credit: Tane Sinclair-Taylor/ARC Center of Excellence.

Furthermore, the scientists behind this study have found that 91% of Australia's Great Barrier Reef has been bleached at least once during those three major bleaching events. Also, during their long-term studies on coral reefs, the team has concluded that it is not possible to stop bleaching locally, by controlling water quality and fishing. According to the scientists, all we have at hand is to do something about climate change. As stated by Professor Hughes:

"I think it's a wake-up call. We've been hoping that local interventions with water quality and fishing would improve the resistance of the corals to bleaching. We found no evidence that that's actually true, at least during a very severe event."

It is yet to be seen how badly this year’s bleaching event will rank in the records.

Fluorescence is the ability to absorb light at short wavelengths and re-emit it at longer wavelengths, which differs from bioluminescence because it relies on the absorption of light instead of chemical reactions to generate light. This ability was already observed in many ocean creatures, including corals, fish, and sharks, but far less common in land creatures and never before in amphibians.

That is no longer the case. It was found this week that the polka dot tree frog (Hypsiboas punctatus), which under normal light sports tones of green, yellow, and red, can emit a bright blue and green glow if illuminated by ultraviolet light only. According to marine biologist David Gruber of Baruch College, from the City University of New York:

"I think it’s exciting. It opens up many more questions than are answered."

More interesting is the fact that this fluorescence is created by completely different molecules than those found in other animals. According to Norberto Peporine Lopes, a chemist at the University of São Paulo in Brazil, the three molecules responsible for the green fluorescence have closely similar molecules found in plants, not animals.

Finally, the observed luminescence was surprisingly strong, providing as much as 18% of the visible light emitted by a full moon.

Even though computer processors have become more reliable and faster over time, manufacturers can't precisely determine if the structure of their chips conforms to the specifications. This happens because imaging methods can't resolve as much as needed, or are destructive. But researchers from the Paul Scherrer Institute (PSI) have used a method called X-ray tomography to create the most detailed 3D images to-date of a commercially available computer chip.

As can be seen from the video below, a small piece of the processor with 45 nanometers wide wires was recreated in detail by the technique. Now, the team of scientists want to improve the method to scan a complete chip.

Another achievement of the team was to obtain images with far fewer distortions than those obtained by current methods. These results were reported in the scientific journal Nature.

The LHCb experiment is one of the main experiments being developed at CERN, in the frontier between France and Switzerland. It is equipped with a precise detector capable of recognizing different types of particles and has already captured a huge amount of data during the first and second runs of the Large Hadron Collider.

While exploring this large and detailed dataset, scientists have found a new system of five particles by tracing back the final configuration of a collision, recreating the initial event. Being able to observe all five new states at once is considered as a rather unique event by scientists.

The new particles are excited states of an Omega-c-zero particle, which means they are more energetic than the particle’s ground state. The Omega-c-zero decays into a Xi-c-plus and a kaon, which in turn decays into a proton, another kaon, and a pion. By reversing this decay process, scientists were able to determine the existence of the Ωc(3000)0, Ωc(3050)0, Ωc(3066)0, Ωc(3090)0, and Ωc(3119)0 particles.

Finally, scientists will now determine the quantum numbers of these new particles, which will be used to identify the properties of each one of them.

As reported here at Neowin last Tuesday, a paper published in Nature Photonics by a team of scientists from the University of Michigan has reported how our electronics could become 100,000 times faster than those commonly found today. The team has used ultra-fast laser impulses to move electrons around so fast they no longer bump into each other, which improves both performance and energy-efficiency. Finally, further tests by the scientists may have provided a new framework for developing a quantum computer.